Control of Mediated Reality Welding System Based on Lighting Conditions

ABSTRACT

An example head-worn device includes a camera, a display device, weld detection circuitry, and pixel data processing circuitry. The camera generates first pixel data from a field of view of the head-worn device. The display device displays second pixel data to a wearer of the head-worn device based on the first pixel data captured by the camera. The weld detection circuitry determines whether a welding arc is present and generates a control signal indicating a result of the determination. The pixel data processing circuitry processes the first pixel data captured by the camera to generate the second pixel data for display on the display device, where a mode of operation of said pixel data processing circuitry is selected from a plurality of modes based on said control signal.

RELATED APPLICATIONS

This patent application is a continuation-in-part of U.S. patentapplication Ser. No. 14/669,380, filed Mar. 26, 2015, and entitled“Control of Mediated Reality Welding System Based on LightingConditions.” The entirety of U.S. patent application Ser. No. 14/669,380is incorporated herein by reference.

BACKGROUND

Welding is a process that has increasingly become ubiquitous in allindustries. While such processes may be automated in certain contexts, alarge number of applications continue to exist for manual weldingoperations, the success of which relies heavily on the ability of theoperator to see his/her work while protecting his/her eyesight.

BRIEF SUMMARY

Methods and systems are provided for control of mediated reality weldingsystem based on lighting conditions, substantially as illustrated byand/or described in connection with at least one of the figures, as setforth more completely in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an exemplary arc welding system in accordance with aspectsof this disclosure.

FIG. 2 shows example welding headwear in accordance with aspects of thisdisclosure.

FIG. 3A shows example circuitry of the welding headwear of FIG. 2.

FIG. 3B shows example circuitry of the welding headwear of FIG. 2.

FIG. 3C shows example circuitry of the welding headwear of FIG. 2.

FIG. 4 shows example optical components of the welding headwear of FIG.2.

FIG. 5 is a flowchart illustrating an example process for controllingpixel data processing in the headwear of FIG. 2.

FIGS. 6A and 6B are block diagrams of example circuitry for controllingpixel data processing based on a detection of light intensity.

DETAILED DESCRIPTION

As utilized herein the terms “circuits” and “circuitry” refer tophysical electronic components (i.e. hardware) and any software and/orfirmware (“code”) which may configure the hardware, be executed by thehardware, and or otherwise be associated with the hardware. As usedherein, for example, a particular processor and memory may comprise afirst “circuit” when executing a first one or more lines of code and maycomprise a second “circuit” when executing a second one or more lines ofcode. As utilized herein, “and/or” means any one or more of the items inthe list joined by “and/or”. As an example, “x and/or y” means anyelement of the three-element set {(x), (y), (x, y)}. In other words, “xand/or y” means “one or both of x and y”. As another example, “x, y,and/or z” means any element of the seven-element set {(x), (y), (z), (x,y), (x, z), (y, z), (x, y, z)}. In other words, “x, y and/or z” means“one or more of x, y and z”. As utilized herein, the term “exemplary”means serving as a non-limiting example, instance, or illustration. Asutilized herein, the terms “e.g.,” and “for example” set off lists ofone or more non-limiting examples, instances, or illustrations. Asutilized herein, circuitry is “operable” to perform a function wheneverthe circuitry comprises the necessary hardware and code (if any isnecessary) to perform the function, regardless of whether performance ofthe function is disabled or not enabled (e.g., by a user-configurablesetting, factory trim, etc.).

Disclosed example head-worn devices include a camera to generate firstpixel data from a field of view of the head-worn device; a displaydevice to display second pixel data to a wearer of the head-worn devicebased on the first pixel data captured by the camera; weld detectioncircuitry to: determine whether a welding arc is present; and generate acontrol signal indicating a result of the determination; and pixel dataprocessing circuitry to process the first pixel data captured by thecamera to generate the second pixel data for display on the displaydevice, wherein a mode of operation of said pixel data processingcircuitry is selected from a plurality of modes based on said controlsignal.

Some example head-worn devices further include a receiver circuit toreceive a communication, in which the weld detection circuitrydetermines whether the welding arc is present based on thecommunication. In some examples, the weld detection circuitry detects anelectromagnetic field associated with the welding arc and determineswhether the welding arc is present based on the electromagnetic field.

In some examples, the weld detection circuitry receives a signalrepresentative of a weld current flowing through a weld torch anddetermines whether the welding arc is present based on the signal. Insome such examples, the mode of operation of the pixel data processingcircuitry is selected based on a weld current level indicated by thesignal. In some such examples, the signal includes a communication fromat least one of a welding-type power supply, a wire feeder, or awelding-type torch.

Some example head-worn devices further include a microphone to receivean audio signal, in which at least one of processing the first pixeldata or the mode of operation of the pixel data processing circuitry isbased on the audio signal. In some examples, the weld detectioncircuitry determines whether the welding arc is present based onreceiving a signal indicative of whether the welding arc is present. Insome examples, the weld detection circuitry receives one or more signalsfrom a corresponding one or more of a temperature sensor, anaccelerometer, a touch sensor, or a gesture sensor, and determineswhether the welding arc is present based on the one or more signals. Insome examples, the display device overlays the second pixel data over areal view to create an augmented reality view for the wearer of thedisplay device.

Disclosed example head-worn devices include: a display device to displaypixel data to a wearer of the head-worn device; weld detection circuitryto determine whether a welding arc is present and generate a controlsignal indicating a result of the determination; and pixel dataprocessing circuitry to generate the pixel data for display on thedisplay device based on the control signal to provide an augmentedreality display.

In some examples, a mode of operation of the pixel data processingcircuitry is selected from a plurality of modes based on said controlsignal. In some examples, one or more objects from a set ofpredetermined objects are rendered for output on the display device bythe pixel data processing circuitry based on said control signal. Insome examples, the display device displays the pixel data such thatpixels defined in the pixel data are overlaid onto a real view throughthe display device. In some such examples, the display device displaysthe pixel data such that at least a portion of the display device istransparent, in which the portion of the display device corresponds toundefined pixels in the pixel data or pixels defined in the pixel dataas transparent.

Some example head-worn devices further include a receiver circuit toreceive a communication, in which the weld detection circuitrydetermines whether the welding arc is present based on thecommunication. In some examples, the weld detection circuitry detects anelectromagnetic field associated with the welding arc and determineswhether the welding arc is present based on the electromagnetic field.

In some examples, the weld detection circuitry receives a signalrepresentative of a weld current flowing through a weld torch anddetermines whether the welding arc is present based on the signal. Someexample head-worn devices further include a microphone to receive anaudio signal, in which at least one of the processing the pixel data ora mode of operation of the pixel data processing circuitry is based onthe audio signal. In some examples, the weld detection circuitryreceives one or more signals from a corresponding one or more of atemperature sensor, an accelerometer, a touch sensor, or a gesturesensor, and determines whether the welding arc is present based on theone or more signals.

Referring to FIG. 1, there is shown an example welding system 10 inwhich an operator 18 is wearing welding headwear 20 and welding aworkpiece 24 using a torch 27 to which power or fuel is delivered byequipment 12 via a conduit 14. The equipment 12 may comprise a power orfuel source, optionally a source of an inert shield gas and, wherewire/filler material is to be provided automatically, a wire feeder. Thewelding system 10 of FIG. 1 may be configured to form a weld joint byany known technique, including flame welding techniques such as oxy-fuelwelding and electric welding techniques such as shielded metal arcwelding (i.e., stick welding), metal inert gas welding (MIG), tungsteninert gas welding (TIG), and resistance welding.

Optionally in any embodiment, the welding equipment 12 may be arcwelding equipment that provides a direct current (DC) or alternatingcurrent (AC) to a consumable or non-consumable electrode of a torch 27.The electrode delivers the current to the point of welding on theworkpiece 24. In the welding system 10, the operator 18 controls thelocation and operation of the electrode by manipulating the torch 27 andtriggering the starting and stopping of the current flow. When currentis flowing, an arc 26 is developed between the electrode and theworkpiece 24. The conduit 14 and the electrode thus deliver current andvoltage sufficient to create the electric arc 26 between the electrodeand the workpiece. The arc 26 locally melts the workpiece 24 and weldingwire or rod supplied to the weld joint (the electrode in the case of aconsumable electrode or a separate wire or rod in the case of anon-consumable electrode) at the point of welding between electrode andthe workpiece 24, thereby forming a weld joint when the metal cools.

FIG. 2 shows example welding headwear in accordance with aspects of thisdisclosure. The example headwear 20 is a helmet comprising a shell 206in or to which is mounted circuitry 200, example details of which areshown in FIGS. 3A-3C. In other implementations, some or all of thecircuitry 200 may not be in headwear but may be in, for example, awelding torch, welding power supply, welding apron, welding gloves,and/or any other welding related accessory.

In FIGS. 3A-3C the circuitry 200 comprises user interface controls 314,user interface driver circuitry 308, a control circuit 310, speakerdriver circuitry 312, speaker(s) 328, cameras 316 a and 316 b, graphicsprocessing unit (GPU) 318, display driver circuitry 320, and display326. In other embodiments, rather than a helmet, the headwear may be,for example, a mask, glasses, goggles, an attachment for a mask, anattachment for glasses, an attachment for goggles, or the like.

The user interface controls 314 may comprise, for example, one or moretouchscreen elements, microphones, physical buttons, and/or the likethat are operable to generate electric signals in response to userinput. For example, user interface controls 314 may comprise capacitive,inductive, or resistive touchscreen sensors mounted on the back of thedisplay 326 (i.e., on the outside of the helmet 20) that enable a wearerof the helmet 20 to interact with user graphics displayed on the frontof the display 326 (i.e., on the inside of the helmet 20).

The user interface driver circuitry 308 is operable to condition (e.g.,amplify, digitize, etc.) signals from the user interface component(s)314 for conveying them to the control circuit 310.

The control circuitry 310 is operable to process signals from the userinterface driver 308, the GPU 318, and the light sensor 324 (FIG. 3A) orone or both of the cameras 316 a and 316 b (FIG. 3C). Signals from theuser interface driver 308 may, for example, provide commands for settingvarious user preferences such as display settings (e.g., brightness,contrast, saturation, sharpness, gamma, etc.) and audio output settings(e.g., language, volume, etc.). Signals from the GPU 318 may comprise,for example, information extracted from pixel data processed by the CPU,current settings/state/etc. of the GPU 318, and/or the like. Signalsfrom the cameras 316 a and 316 b (FIG. 3C) may comprise, for example,information extracted from pixel data captured by the cameras, currentsettings/state/etc. of the cameras 316, and/or the like.

The control circuit 310 is also operable to generate data and/or controlsignals for output to the speaker driver 312, the GPU 318, and thecameras 316 a and 316 b (FIGS. 3A and 3C). Signals to the speaker driver312 may comprise, for example, audio data for output via the speakers328, control signals to adjust settings (e.g., volume) of the outputaudio, and/or the like. Signals to the GPU 318 may comprise, forexample, control signals to select and/or configure pixel dataprocessing algorithms to perform on the pixel data from the cameras 316a and 316 b. Signals to the cameras 316 may comprise, for example,control signals to select and/or configure shutter speed, f-number,white balance, and/or other settings of the cameras 316.

The speaker driver circuitry 312 is operable to condition (e.g., convertto analog, amplify, etc.) signals from the control circuitry 310 foroutput to one or more speakers of the user interface components 208.

The cameras 316 a and 316 b are operable to capture electromagneticwaves of, for example, infrared, optical, and/or ultravioletwavelengths. Each of cameras 316 a and 316 b may, for example, comprisean optical subsystem and two sets of one or more image sensors (e.g.,two sets of one image sensor for monochrome or two sets of three imagesensors for RGB). The two sets of optics may be arranged to capturestereoscopic pixel data such that the resulting images presented ondisplay 326 appear to the wearer of headwear 20 as if seen directly byhis/her eyes.

FIG. 3C illustrates additional sources of data that are usable by thecontrol circuit 310 to determine whether a welding arc is present. Inthe example of FIG. 3C, the circuitry 200 may include one or more ofreceiver circuitry 300, a current sensor 332, a field sensor 334, amicrophone 336, and/or one or more sensor(s) 338, such as a temperaturesensor, an accelerometer, a touch sensor, and/or a gesture sensor. As analternative to detecting a welding arc via the cameras 316 a or 316 band/or via the light sensor 324 (FIG. 3b ), the example control circuit310 receives one or more signals from the receiver circuitry 330, acurrent sensor 332, a field sensor 334, a microphone 336, and/or one ormore sensor(s) 338 and determines whether the welding arc is presentbased on the received signals.

The receiver circuitry 330 receives a communication or other signal thatindicates whether a weld current is flowing through the weld torch. Asignal or communication may be received from, for example, an externalcurrent sensor, a weld torch trigger, a wire feeder, and/or any otherdevice capable of detecting or measuring current in the weld circuit.When a signal or communication is received at the receiver circuitry330, the control circuit 310 determines whether the welding arc ispresent based on the communication.

The current sensor 332 may provide a signal to the control circuit 310that is representative of a weld current flowing through a weld torch.Based on the signal, the control circuit 310 determines whether thewelding arc is present based on the signal. In some examples, the modeof operation of the pixel data processing circuitry is selected based onthe weld current level indicated by the signal output from the currentsensor 332. The signal may include a communication from at least one ofa welding-type power supply, a wire feeder, or a welding-type torch. Themode of operation may be selected based on a weld current levelindicated by the signal.

The field sensor 334 detects an electromagnetic field associated withthe welding arc. For example, the field sensor 334 may be coupled to anantenna to identify one or more frequencies of interest that correspondto a welding arc. The control circuit 310 may determine whether thewelding arc is present based on the electromagnetic field and/or thefrequency components of the electromagnetic field detected by the fieldsensor 334.

The microphone 336 receives audio signal(s). Welding is associated withidentifiable sounds. The control circuit 310 and/or the GPU 318 mayprocess the pixel data and/or select a mode of operation based onprocessing the audio signal.

The control circuit 310 may receive one or more signals from the one ormore sensors 338. For example, the control circuit 310 may receivesignals from the temperature sensor (e.g., infrared temperature near theworkpiece), an accelerometer (e.g., torch orientation and/or torchmovement information), a touch sensor (e.g., holding a welding torchand/or touching the torch trigger), and/or a gesture sensor (e.g.,recognizing a gesture associated with an operator welding). The controlcircuit 310 determines whether the welding arc is present based on theone or more signals from the one or more sensors.

Referring briefly to FIG. 4, an example implementation of a camera 316is shown. The example implementation of the camera 316 shown in FIG. 4comprises lenses 410, beam splitter 412, image sensors 408 a and 408 b,control circuitry 414, and input/output circuitry 416. The image sensors408 a and 408 b comprise, for example, CMOS or CCD image sensorsoperable to convert optical signals to digital pixel data and output thepixel data to input/output circuit 416. The input/output circuit 416 mayoutput the pixel data in serial or parallel in accordance with protocolsagreed on between the camera 316 and the GPU 318. The control circuitry414 is operable to generate signals for configuring/controllingoperation of the image sensors 408 a and 408 b and I/O circuit 416. Thecontrol circuit 414 may be operable to generate such control signalsbased on other control signals received from, for example, light sensor324 and/or control circuit 310.

In operation, light beams 402 are focused onto beam splitter 412 bylenses 410. A first portion of beams 402 are reflected by the splitter412 to arrive at image sensor 408 a as beams 406. A second portion ofbeams 402 pass through the splitter 412 to arrive at image sensor 408 bas beams 404. The image sensors 408 a and 408 b concurrently capture(i.e., their respective shutters are open for overlapping time periods)respective frames of the same image, but with different settings (e.g.,different shutter speeds). The pixel data streams are then output to I/Ocircuit 416 which, in turn, relays them to GPU 318. The GPU 318 may thencombine the two pixel streams to, for example, achieve an image withcontrast that is better than can be achieved by either of the imagesensors 408 a and 408 individually. The example shown is a monochromeimplementation since there is only one image sensor for beams 404 andone image sensor for beams 406. In an example color implementation,beams 404 may be further split and pass through color-selective filtersin route to a plurality of image sensors 408 b and beams 406 may befurther split and pass through color-selective filters in route to aplurality of image sensors 408 a.

In another example implementation, sufficient contrast may be achievedwith only a single image sensor 408 (or set of image sensors 408 forcolor) per camera 316. This may be achieved, for example, with a highdynamic range image sensor or simply result from the fact thatrelatively lower dynamic range is sufficient in some applications (e.g.,in an augmented reality application where the pixel data is overlaid onthe real view instead of a mediated reality in which everything theviewer sees is a processed image).

Likewise, in some example implementations, stereo vision may not beneeded and thus only a single camera 316 may be used.

Returning to FIGS. 3A-3C, the light sensor 324 (FIGS. 3A and 3B)comprises circuitry operable to measure the intensity of light incidenton the headwear 20. The light sensor 324 may comprise, for example, aphotodiode or passive infrared (IR) sensor, along with associated driveelectronics (e.g., amplifiers, buffers, logic circuits, etc.). Themeasured intensity (e.g., measured in candelas) may be used to determinewhen a welding arc is struck. In an example implementation, there may bemultiple light sensors 324 which sense light intensity from multipledirections. For example, a first sensor 324 may sense the intensity oflight incident on the front of the headwear 20 (light which may bedirectly incident on the headwear 20 from a welding arc) and a secondsensor may sense the intensity of light incident on the back of theheadwear 20 (which may be shielded from direct light from the weldingarc). The different readings from various light sensors 324 may be usedto determine information about the lighting environment, which may, inturn, be used for controlling the pixel data processing algorithms usedfor processing pixel data from the cameras 316 a and 316 b forpresentation on the display 326.

The graphics processing unit (GPU) 318 is operable to receive andprocess input pixel data from the cameras 316 a and 316 b. Theprocessing of pixel data by the GPU 318 may extract information from thepixel data and convey that information to control circuit 310. Theprocessing of pixel data by the GPU 318 may result in the generation ofoutput pixel data for conveyance to the display driver 320. In anexample implementation, the pixel data output from the GPU 318 to thedisplay driver 320 (and ultimately to display 326) may provide amediated-reality view for the wearer of the headwear 20. In such a view,the wearer experiences the video presented on the display 326 as if s/heis looking through a lens, but with the image enhanced and/orsupplemented by an on-screen display. The enhancements (e.g., adjustcontrast, brightness, saturation, sharpness, gamma, etc.) may enable thewearer of the helmet 20 to see things s/he could not see with simply alens (e.g., through contrast control). The on-screen display maycomprise text, graphics, etc. overlaid on the video to, for example,provide visualizations of equipment settings received from the controlcircuit 310 and/or visualizations of information determined from theanalysis of the pixel data. In another example implementation, the pixeldata output from the GPU 318 may be overlaid on a real view seen througha transparent or semi-transparent lens (such as an auto-darkening lensfound on conventional welding headwear). Such overlaid information maycomprise text, graphics, etc. overlaid on the video to, for example,provide visualizations of equipment settings received from the controlcircuit 310 and/or visualizations of information determined from theanalysis of the pixel data.

In an example implementation, the processing of pixel data by the GPU318 may comprise the implementation of pixel data processing algorithmsthat, for example, determine the manner in which multiple input streamsof pixel data from multiple cameras 316 are combined to form a singleoutput stream of pixel data. Configuration of pixel data processingalgorithms performed by GPU 318 may comprise, for example, configurationof parameters that determine: characteristics (e.g., brightness, color,contrast, sharpness, gamma, etc.) of the streams prior to combining;characteristics (e.g., brightness, color, contrast, sharpness, gamma,etc.) of the combined stream; and/or weights to be applied to pixel datafrom each of the multiple streams during weighted combining of themultiple streams. In an example implementation using weighted combiningof input pixel streams, the weights may be applied, for example, on apixel-by-pixel basis, set-of-pixels-by-set-of-pixels basis,frame-by-frame basis, set-of-frames-by-set-of-frames basis, or somecombination thereof. As one example, consider weighted combining ofthree frames of two input pixel streams where weights of 0, 1 are usedfor the first frame, weights 0.5, 0.5 are used for the second frame, andweights 1, 0 are used for the third frame. In this example, the firstframe of the combined stream is the first frame of the second inputstream, the second frame of the combined stream is the average of thesecond frames of the two input streams, and the third frame of thecombined stream is the third frame of the first input stream. As anotherexample, consider weighted combining of three pixels of two input pixelstreams where weights of 0, 1 are used for the first pixel, weights 0.5,0.5 are used for the second pixel, and weights 1, 0 are used for thethird pixel. In this example, the first pixel of the combined stream isthe first pixel of the second input stream, the second pixel of thecombined stream is the average of the second pixels of the two inputstreams, and the third pixel of the combined stream is the third pixelof the first input stream.

As mentioned above, in other implementations, stereovision may not beneeded and thus a single camera 316 may be sufficient. Also, in someimplementations, sufficient contrast may be achieved with a single (orsingle set) of image sensors and there may be no need for the combiningof bright and dark pixel streams to enhance contrast. As an example,where it is desired to capture pixel data only when the welding arc ispresent (as indicated by the light sensor 324), then the system may useonly a single camera 316 with single image sensor (or set of imagesensors for color) configured for capturing pixel data in the presenceof the arc.

In other example implementations, no cameras 316 at all may be present.This may include, for example, an augmented reality application in whichpixel data comprising only predetermined objects (e.g., graphics, text,images captured by means other than the headwear 20, etc.) is renderedfor output onto the display 306. Which objects are rendered, and/orcharacteristics (e.g., color, location, etc.) of those objects, maychange based on whether the light sensor indicates the arc is present ornot. In some examples, the display 306 overlays pixel data of renderedobjects over a real view to create an augmented reality view for thewearer of the display 306.

The display driver circuitry 320 is operable to generate control signals(e.g., bias and timing signals) for the display 326 and to process(e.g., level control synchronize, packetize, format, etc.) pixel datafrom the GPU 318 for conveyance to the display 326.

The display 326 may comprise, for example, two (in implementations usingstereoscopic viewing) LCD, LED, OLED, E-ink, and/or any other suitabletype of panels operable to convert electrical pixel data signals intooptical signals viewable by a wearer of the helmet 20.

In operation, a determination of the intensity of light incident on thecameras 316 a and 316 b during capture of a pair of frames may be usedfor configuring the pixel data processing algorithm that performscombining of the two frames and/or may be used for configuring settingsof the camera 316 a and 316 b for capture of the next pair of frames.

In the example implementations of FIGS. 3A and 3B, the light intensityis measured by one or more light sensors 324. Each light sensor maycomprise, for example a photodiode or passive IR sensor that issensitive to wavelengths in the visible spectrum. The measurement fromthe light sensor(s) 324 may then be used to configure pixel data capturesettings (e.g., shutter speeds, f-numbers, white balance, etc.) of thecameras 316 a and 316 b. Additionally, or alternatively, the measurementfrom the light sensor(s) 324 may be used to select and/or configurepixel data processing algorithms performed on the captured pixel data bythe GPU 318. In the example implementation of FIG. 3A, the measurementmay be conveyed to the control circuit 310 which may then perform theconfiguration of the cameras 316 a and 316 b and/or the GPU 318. In theexample implementation of FIG. 3B, the measurement from the lightsensor(s) 324 may be conveyed directly to the cameras 316 a and 316 band/or GPU 318, which may then use the measurement to configurethemselves.

In the example implementation of FIG. 3C, rather than using a lightsensor 324 that is distinct from the image sensors 408 a and 408 b, ameasurement of light intensity is generated based on the pixel datacaptured by the cameras 316 a and 316 b. For example, each camera maycalculate average luminance over groups of pixels of a frame and/orgroups of frames. The calculated luminance value(s) may then be conveyedto the control circuit 310 and/or GPU 318 which may then configure thesettings of the cameras 316 a and 316 b and/or configure the pixel dataprocessing algorithms used to combine the pixel data from the two imagesensors. The cameras 316 a and 316 b may also use the calculatedluminance value(s) in a feedback loop for configuring their settings(such as timing and/or speed of an electronic and/or mechanical shutter,and/or some other electric, mechanical, or electromechanical operationor system in the cameras 316 a and 316 b).

Operation of the various implementations shown in FIGS. 3A-3D is nowdescribed with reference to FIG. 5.

In block 502, two frames are captured by the cameras 316 a and 316 b.The cameras 316 a and 316 b are synchronized such that the two framesare captured simultaneously (within an acceptable timing tolerance). Thetwo frames are captured with different settings such that they providediversity of captured information. For example, image sensor 416 a mayuse a slower shutter speed and/or lower f-number (and be referred toherein as the “bright image sensor”) and the image sensor 416 b may usea faster shutter speed and/or higher f-number (and be referred to hereinas the “dark image sensor”). As an example, for frames captured while awelding arc is very bright, the bright image sensor may be overexposedwhile the dark image sensor provides an image that provides sufficientcontrast for the wearer of the headwear 20 to clearly see the weld pool,arc, weld metal, workspace, and weld joint surroundings such that s/hecan lay down a high-quality weld. Continuing this example, for framescaptured while a welding arc is not present, the dark image sensor maybe underexposed while the bright image sensor provides an image thatprovides sufficient contrast for the wearer of the headwear 20 toclearly see the weld pool, arc, weld metal, workspace, and weld jointsurroundings such that s/he can lay down a high-quality weld.

In block 504, the light intensity incident on the cameras 316 a and 316b during capture of a pair of frames is determined through directmeasurement or indirect measurement. Direct measurement may comprise,for example, measurement by one or more light sensors 324 (FIGS. 3A and3B) and/or the image sensors 408 a and 408 b. An example of indirectmeasurement is use of an arc monitoring tool to measure amperagedelivered from the torch 204 to the workpiece 24 and then calculatinglux based on the measured amperage, the type of torch, type of workpiece(e.g., type of metal), etc.

In block 506, the intensity of light measured in block 504 is comparedto a determined threshold. The threshold may be fixed or may be dynamic.An example where the threshold is dynamic is where the threshold isadapted through one or more feedback loops (e.g., based on lightintensity measured during previously-captured frames). Another examplewhere the threshold is dynamic is where it is configurable based oninput from user interface controls 314 (e.g., a user may adjust thethreshold based on his/her preferences). In an example implementation,the threshold is set such that the comparison distinguishes betweenframes captured while a welding arc was struck and frames capture whenno welding arc was present. If the light intensity measured in block 504is above the threshold, then the process advances to block 508.

In block 508, the GPU 318 processes the frames of pixel data fromcameras 316 a and 316 b using a first one or more algorithms and/or afirst one or more parameters values. The one or more algorithms may beselected from a larger set of algorithms available to the GPU 318 and/orthe first one or more parameter values may be selected from a larger setof possible values. In this manner, the algorithms, and/or parametervalues used thereby, are determined based on the result of thecomparison of block 506.

In block 512, the process pixel data is output from GPU 318 to displaydriver 320.

Returning to block 506, if the intensity of light measured in block 504is not above the threshold, then the process advances to block 510.

In block 510, the GPU 318 processes the frames of pixel data fromcameras 316 a and 316 b using a second one or more algorithms and/or asecond one or more parameter values. The one or more algorithms may beselected from a larger set of algorithms available to the GPU 318 and/orthe first one or more parameter values may be selected from a larger setof possible values. In this manner, the algorithms, and/or parametervalues used thereby, are determined based on the result of thecomparison of block 506.

In an example implementation, block 508 corresponds to simply selectingone of the two frames from cameras 316 a and 316 b and discarding theother of the two frames, and block 510 corresponds to combining the twoframes to form a new combined frame (e.g., where the combined frame hashigher contrast than either of the two original frames).

In an example implementation, block 508 corresponds to applying a firstset of pixel post-processing parameter values (e.g., for adjustingbrightness, color, contrast, saturation, gamma, etc.) to the two framesduring combining of the two frames, and the block 510 corresponds toapplying a second set of pixel post-processing parameter values to thetwo frames during combining of the two frames.

FIGS. 6A and 6B are block diagrams of example circuitry for controllingpixel processing based on a detection of light intensity. Shown in FIGS.6A and 6B are pixel data processing circuitry 602 and light intensitydetection circuitry 604. The pixel data processing circuitry 602 maycomprise, for example, circuitry the GPU 318, circuitry of the camera(s)316, display driver circuitry 320, and/or circuitry of the display 326.The light intensity detection circuitry 604 may comprise, for example,the light sensor 324, circuitry of the GPU 318, and/or circuitry of thecamera(s) 316. In the implementation of FIG. 6B, the light intensitydetection circuitry 604 also processes pixel data and may be consideredpixel data processing circuitry in such an implementation.

In FIG. 6A, the light intensity detection circuitry 604 directlycaptures light incident on it and sets the value of control signal 605based on the intensity of the light according to some function, logicoperation, etc. For example, in FIG. 6A the light intensity detectioncircuitry 604 may comprise a photodiode or passive IR sensor that ismounted on the outside of the headwear 20 facing the likely direction ofthe welding arc. The light detection circuitry 604 may, for example,convert (e.g., through any suitable circuitry such as an ADC, acomparator, etc.) the light incident on it to a 1-bit signal 605 thatindicates arc weld present or absent. As another example, the signal 605may be an analog signal or multi-bit digital signal capable ofrepresenting additional decision levels (e.g., 2 bits for arc definitelyabsent, arc probably absent, arc probably present, and arc definitelypresent; myriad other possibilities of course exist). The pixel dataprocessing circuitry 602 receives the signal 605 and configures theoperations it performs on the pixel data in response to the state ofsignal 605. For example, when signal 605 is low, indicating the arc isabsent, the pixel data processing circuitry may process the pixel streamin a first manner (e.g., using a first set of weighting coefficients forcombining two pixel streams) and when signal 605 is high, indicating thearc is present, the pixel data processing circuitry may process thepixel stream in a second manner (e.g., using a second set of weightingcoefficients for combining two pixel streams).

FIG. 6B is similar to FIG. 6A but with the light intensity detectioncircuitry 604 determining intensity from the pixel data itself. Forexample, the light intensity detection circuitry 604 may compare thepixel values (e.g., on a pixel-by-pixel basis,pixel-group-by-pixel-group basis, or the like) to determine whether thearc was present during the capture of the pixel(s) currently beingprocessed.

In an implementation such as FIG. 6B, the light detection circuitry 604may be fast enough such that it is able to make its decision andconfigure the signal 605 without requiring the pixel data to be bufferedlonger than would introduce a noticeable lag. In this regard, in someinstances the circuitry 604 may be capable of generating a decision andconfiguring signal 605 within a single pixel clock cycle, thus avoidingneed for any additional buffering of the pixel data stream.

In accordance with an example implementation of this disclosure, asystem (e.g., a welding system comprising one or both of headwear 20 andequipment 12) comprises light intensity detection circuitry (e.g., 604)and multi-mode circuitry (e.g., any one or more of 308, 312, 314, 316,318, 320, 324, and may support multiple modes of operation). The lightintensity detection circuitry is operable to determine whether a weldingarc is present based on an intensity of light incident captured by thelight intensity detection circuitry, and generate a control signal(e.g., 605) indicating a result of the determination. A mode ofoperation of the multi-mode circuitry may be selected from a pluralityof modes based on the control signal. The light intensity detectioncircuitry may comprise, for example, a passive infrared sensor, aphotodiode, and/or circuitry of a camera. The multi-mode circuitry maycomprise pixel data processing circuitry (circuitry the GPU 318,circuitry of the camera(s) 316, display driver circuitry 320, and/orcircuitry of the display 326). The pixel data processing circuitry maycomprise, for example, circuitry of a camera, a special purpose graphicsprocessing unit (e.g., 318), and/or a general purpose processing unit. Afirst of the plurality of modes may use a first exposure value and asecond of the plurality of modes use a second exposure value. A first ofthe plurality of modes may use a first set of weights during weightedcombining of pixel data, and a second of the plurality of modes uses asecond set of weights during said weighted combining of pixel data. Aparticular pixel processing operation performed by the pixel dataprocessing circuitry may be disabled when the pixel data processingcircuitry is in a first of the plurality of modes, and enabled when thepixel data processing circuitry is in a second of the plurality ofmodes. Recording of image data by the system may be disabled when thepixel data processing circuitry is in a first of the plurality of modes,and enabled when the pixel data processing circuitry is in a second ofthe plurality of modes. The light intensity detection circuitry may beoperable to update the control signal on a pixel-by-pixel and/orgroup-of-pixels-by-group-of-pixels basis. Other examples of controllingmodes of multi-mode circuitry for providing feedback to the wearercomprise: selecting between on, off, and flashing modes of an LED of theheadwear; and selecting between different sounds to be played through aspeaker of the headwear.

While the example of the two cameras being configured differently interms of exposure value is used in this disclosure for purposes ofillustration, the configurations of the two image sensors need notdiffer in, or only in, exposure value. For example, the first camera beconfigured to have a first shutter timing (that is, when a capture bythat camera is triggered) and the second camera may be configured tohave a second shutter timing. In such an implementation, for example,the amount of light reaching the camera's image sensors may varyperiodically and the two cameras may be synchronized to different phasesof the varying light. While this example implementation is used oftenreferred to in this disclosure for purposes of illustration, the twoconfigurations need not differ in, or only in, exposure value. Forexample, the first configuration may correspond to a first shuttertiming (that is, when a capture is triggered) and the secondconfiguration may correspond to a second shutter timing. In such animplementation, for example, the two image sensors may be synchronizedwith an external light source.

The present method and/or system may be realized in hardware, software,or a combination of hardware and software. The present methods and/orsystems may be realized in a centralized fashion in at least onecomputing system, or in a distributed fashion where different elementsare spread across several interconnected computing systems. Any kind ofcomputing system or other apparatus adapted for carrying out the methodsdescribed herein is suited. A typical combination of hardware andsoftware may be a general-purpose computing system with a program orother code that, when being loaded and executed, controls the computingsystem such that it carries out the methods described herein. Anothertypical implementation may comprise an application specific integratedcircuit or chip. Some implementations may comprise a non-transitorymachine-readable (e.g., computer readable) medium (e.g., FLASH drive,optical disk, magnetic storage disk, or the like) having stored thereonone or more lines of code executable by a machine, thereby causing themachine to perform processes as described herein.

While the present method and/or system has been described with referenceto certain implementations, it will be understood by those skilled inthe art that various changes may be made and equivalents may besubstituted without departing from the scope of the present methodand/or system. In addition, many modifications may be made to adapt aparticular situation or material to the teachings of the presentdisclosure without departing from its scope. Therefore, it is intendedthat the present method and/or system not be limited to the particularimplementations disclosed, but that the present method and/or systemwill include all implementations falling within the scope of theappended claims.

What is claimed is:
 1. A head-worn device, comprising: a cameraconfigured to generate first pixel data from a field of view of thehead-worn device; a display device to display second pixel data to awearer of the head-worn device based on the first pixel data captured bythe camera; weld detection circuitry configured to: determine whether awelding arc is present; and generate a control signal indicating aresult of the determination; and pixel data processing circuitryconfigured to process the first pixel data captured by the camera togenerate the second pixel data for display on the display device,wherein a mode of operation of said pixel data processing circuitry isselected from a plurality of modes based on said control signal.
 2. Thehead-worn device as defined in claim 1, further comprising a receivercircuit configured to receive a communication, the weld detectioncircuitry configured to determine whether the welding arc is presentbased on the communication.
 3. The head-worn device as defined in claim1, wherein the weld detection circuitry is configured to: detect anelectromagnetic field associated with the welding arc; and determinewhether the welding arc is present based on the electromagnetic field.4. The head-worn device as defined in claim 1, wherein the welddetection circuitry is configured to receive a signal representative ofa weld current flowing through a weld torch and to determine whether thewelding arc is present based on the signal.
 5. The head-worn device asdefined in claim 4, wherein the mode of operation of the pixel dataprocessing circuitry is selected based on a weld current level indicatedby the signal.
 6. The head-worn device as defined in claim 4, whereinthe signal comprises a communication from at least one of a welding-typepower supply, a wire feeder, or a welding-type torch.
 7. The head-worndevice as defined in claim 1, further comprising a microphone to receivean audio signal, at least one of the processing the first pixel data orthe mode of operation of the pixel data processing circuitry being basedon the audio signal.
 8. The head-worn device as defined in claim 1,wherein the weld detection circuitry is configured to determine whetherthe welding arc is present based on receiving a signal indicative ofwhether the welding arc is present.
 9. The head-worn device as definedin claim 1, wherein the weld detection circuitry is configured to:receive one or more signals from a corresponding one or more of atemperature sensor, an accelerometer, a touch sensor, or a gesturesensor; and determine whether the welding arc is present based on theone or more signals.
 10. The head-worn device as defined in claim 1,wherein the display device is configured to overlay the second pixeldata over a real view to create an augmented reality view for the wearerof the display device.
 11. A head-worn device, comprising: a displaydevice to display pixel data to a wearer of the head-worn device; welddetection circuitry configured to: determine whether a welding arc ispresent; and generate a control signal indicating a result of thedetermination; and pixel data processing circuitry configured togenerate the pixel data for display on the display device based on thecontrol signal to provide an augmented reality display.
 12. Thehead-worn device as defined in claim 11, wherein a mode of operation ofthe pixel data processing circuitry is selected from a plurality ofmodes based on said control signal.
 13. The head-worn device as definedin claim 11, wherein one or more objects from a set of predeterminedobjects are rendered for output on the display device by the pixel dataprocessing circuitry based on said control signal.
 14. The head-worndevice as defined in claim 11, wherein the display device is configuredto display the pixel data such that pixels defined in the pixel data areoverlaid onto a real view through the display device.
 15. The head-worndevice as defined in claim 14, wherein the display device is configuredto display the pixel data such that at least a portion of the displaydevice is transparent, the portion of the display device correspondingto undefined pixels in the pixel data or pixels defined in the pixeldata as transparent.
 16. The head-worn device as defined in claim 11,further comprising a receiver circuit configured to receive acommunication, the weld detection circuitry configured to determinewhether the welding arc is present based on the communication.
 17. Thehead-worn device as defined in claim 11, wherein the weld detectioncircuitry is configured to: detect an electromagnetic field associatedwith the welding arc; and determine whether the welding arc is presentbased on the electromagnetic field.
 18. The head-worn device as definedin claim 11, wherein the weld detection circuitry is configured toreceive a signal representative of a weld current flowing through a weldtorch and to determine whether the welding arc is present based on thesignal.
 19. The head-worn device as defined in claim 11, furthercomprising a microphone to receive an audio signal, at least one of theprocessing the pixel data or a mode of operation of the pixel dataprocessing circuitry being based on the audio signal.
 20. The head-worndevice as defined in claim 11, wherein the weld detection circuitry isconfigured to: receive one or more signals from a corresponding one ormore of a temperature sensor, an accelerometer, a touch sensor, or agesture sensor; and determine whether the welding arc is present basedon the one or more signals.